Shrinking sales in key slices of the digital video game market had a chilling effect on revenue growth last month, though tough comparisons with the previous February and seasonal factors were at play.

After running hot for months, global revenues from downloaded and online games increased just 4 percent year over year to $7.83 billion last month, gaming intelligence firm SuperData Research reports. The figures do not include sales of physical software.

Sustained growth in mobile and console games underscored the worldwide gains, while the pay-to-play, free-to-play and social segments all saw sales decline from the previous February.

Worldwide revenue for mobile games was up 11 percent, though SuperData notes one of the platform’s high-flyers hit a new low.

Blizzard’s digital card game “Hearthstone” saw receipts fall to their lowest level since launching on both Android and Apple iOS devices. Free-to-play games like “Hearthstone” make money by converting users into buyers of premium items and services.

“Recent gameplay decisions have been unpopular with the Hearthstone community, and the result has been a sharp decrease in conversion on mobile,” SuperData said in its monthly report. “Desktop revenue is also down, but to a lesser extent, perhaps due to the more ‘hardcore’ demographic on PC.”

While the broader free-to-play market shrank in February, the decline does not signal a problem for the segment, SuperData CEO Joost van Dreunen told CNBC. Instead, it’s due to a comparison with last February, when sales were unusually high for top title “League of Legends.”

“Free-to-play overall is fine,” he said. “But it’s basically governed by a handful of big titles, and so whatever’s happening in ‘League of Legends,’ that’s going to have a huge effect on the overall market,” he said.

February and March also typically see a bounce in sales of physical titles at retailers, as players complete the games they received during the holidays and trade them in for new products. That saps some money from the digital space, van Dreunen said.

Revenues for PC titles were up about 3 percent in February, while sales of digital games to consoles like Sony‘s PlayStation 4 and Microsoft‘s Xbox One increased 8 percent.

Electronic Arts‘ “FIFA 17” continues to lead the pack on console and saw double-digit revenue growth from last year. Its profitability is being driven by the game’s popular Ultimate Team mode, which is attracting more users, converting them into paying customers and increasing average revenue per user.